Process of making incandescent-electric-lamp filaments.



H. C. PARKER. I PROCESS OF MAKING INCANDESCENT ELECTRIC LAMP FILAMENTS. APPLICATION FILED APR.10,1909.

974,81 2. Patented Nov. 8, 1910.

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UNITED STATES PATENT OFFICE;

HERSCHEL C. PARKER, 01! NEW YORK, N. Y., ASSIGNOR TO PARKER-CLARK ELECTRIC COMPANY, OF NEW YORK, N. Y., A CORBORATION OF NEW JERSEY.

PROCESS OF MAKING INCANDESCENT-ELECTRIC-LAIP FILAKENTB.

Specification Letters Patent.

Patented Nov. 8, 1910.

1'0 all whom it may concern:

Be it known that I, Hnnsounr, C. PARKER, of the city of New York, county of Kings, and State of New York, have invented a new and useful Improvement/"in Processes of Making Incandescent-Electric- Lamp Filaments, of' which the following is a full, clear, and exact description.

My invention relates to improvements in a process of making filaments for incandescent electric lamps, and the object of my invention is to produce a filament having a core either of carbon or metallized carbon with a coating of coherent, metallic chromium.

I have found that if chromium is deposited on a core in a coherent metallic condition, it makes a very satisfactory filament, as it has ahigh melting point, and produces a filament which has a long ,life and low wattage. I am aware that attempts have been made to produce satisfactory chrolhium filaments, but it has been found dif' ficult. to produce a filament on which the coating is a strictly coherent metallic structure. In many attempts, the deposit has been largely carbon or else in the form of, an oxid of chromium, which under certain conditionsresembles the metal, butis useless for li htin' uroses.

lu oi d eir t b accomplish the required resalt, it is necessary to have in the flashing jar an excess of the vapor ofchroniium oxyehlorid and a reducing and chlorin absorbing gas. flhe absorbent for the chlorin must be something for which the chlorin has a' greater ailinity than for the chromium so that when the chlorin is freed it will not recombine. F or this purpose olefiant gas 0 H, seems to be the best gas. though other hydro-carbon gases can be used, such for instance as marsh gas or acetylene. 'Ihe boiling point of chromium oxy-chl0rid which is about 115 degrees centigrade. is so high that a sufiicient amount does-not vaporize into the treating jar directly, and if it -is at temptedto boll it in, the vapor condenses in the treating jar'and is very troublesome. have therefore found that the best. way to introduce this excess of. the chromium oxy: chlorid vapor is to make use of a vaporizer such as shown in the accompanyingdrawing in which 10 is a glass tube w ich is preferably six to twelve inches long and from one to two inches in diameter. An inlet tube =11 controlled by the cock 12 is arran ed near one end of the tube and above t e oxychlor1d contained therein, while an outlet tube 13 controlled by the cock 13" rises from the upper part and opposite end of the tube and connects with the flashing jar 14 which can be of any usual type. The pipe 15, preferably controlled by the cock 16 and connectlng'with a tank 17 of the olefiant gas, also connects with the ipe or tube 13. It is necessary to have t e olefiant gas mix with the hydrogen after the latter has become saturated with the oxy-chlorid vapor,

because if the olefiant gas is first mixed with rangenient shown could be dispensed with,.

but I have found that in practice the arran ement works out perfectl The tube 10 eing oxy-chlori the hydrogen va or is passed over the surface of the li ui sure. lilarge amount of t e vaporis then mechamcally picked up and carried forward into the flashing jar. ehlorid picked up may be increased at Wlll if the outlet from the tube is left wide openwhile the inlet through which the hydrogen enters is constricted.

The pressure which appears to give the best results and to take in a sufficient amount of rhkommm oxyashlorid, is noted to be about twen .y-tive inches. This is the pressure which. passes into the flashing jar. Of this twenty inches, approximately, consists of the artly filled with te chromium.

under pres- The. amount .of oxy-- hydrogen mixed with the vapor of chromium oxy-chlorid, and the balance olefiant 'gas. If a sufficient amount of the chromium oxychlorid, however, is in the treating jar and fiant. gas passed over the chromium oxy'-' chlorid to a pressure of about twent to twenty-five inches, gives good results i -the-- temperature is right, but as stated above, the olefiantgas has a tendency, when passeddirectly over the chromium oxy-chlorid, to

: solidify the same and prevent its vaporization, while pure hydrogen or hydrogen contaming a very small percentage of olefiant gas. does not have this efi'ecthe mixture in the flashing jar should be .0 must be exercised to from five to twenty per cent. olefiant gas. The remainder is hydrogen vslipor saturated with chromium oxy-chlorid. be more exact, I find that I et the best results when the uses in the cabin jar ere approximdte y twent per cent. 0 efiunt gas, seventy per cent. by rogen, and ten per cent.-chromium oxy-chlorid, although as stated, these percentages may be reatly varied. Cure ave the tem erature right. "If the temperature is too ow the chromium comes down in crystalline fiorm. If the tem erature is too high, the olefiant s is broEen u in a carbon deposit. It

6 as been'foun by experiment that the roper temperature will be approximately between one thousand and twelve hundred 'degreescentigrade. I have also found that if the hydro n alone is used, a deposit may I) be brou ht own under these conditions, but

such a mium, which resembles the metal, and as stated before, if the temperature is righ a coatin of metallic appearance maybe a so broug A down, and consists essentially'of 1 carbon. Tp resume I find then that the. best results are obtained by passing the hydrogeii over the oxy-chlori of chromium so ,that'the oxy-chlorid is mechanical] p1clced v up and carried forward to the flas mg 1st, next admitting the olefiar'it gas after the oxy-chlorid has been picked up by the hydrogen, and finally flashingl the fi ament' m the mingled uses and wit a term erature of from one ousand to twelve hun red degrees oentigrade. I find that when this arrangement 18 carried out the flushing1 takes place instantly, andzthat I et a co erent, metallicchromium deposit a over the fila- The olefiant gas besides actin as an absorbent for the chlorin serves a so as a deoxidizingagent, und gen as well as the chlorln, and this 18 nuoitant because 0 n readily attacks n ellic'chromium. 6' flashin of the filamentis performed inthe usua way, that "IS b turning an electric current through it, tlliis" raising it to the temperature of meandcscence, and, as revious y stated, the temerlture should e approximately between 000 and 12009 c.

Having thus full described my invention,

I claim as new an desire to secure by, Let

tersPatenm 1. The herein described process of mak ng incandescent electric lamp filaments, Wh1 consists in flash a filament in an atmosphere consisting o a hydrogen vapor sat-ueposit contains the oxid of chro thus absorbs the oxy-.

consists in flushing the 'pherecontaining in incandescent electric rated with oxy-chiorid of chromium, und with an absorbent gas for tubing up the gases freed by the flushing process.

2. The herein described process of mekin incandescent electric lump filaments, WlllC] consists in flushing a filament in an utmosphere containing hydrogen, oxy-chlorid of chromium and olcfiunt gas.

3. The herein described process of making incandescent electric lump filaments which consists in flushing u carbon filament in an vatmosphere contamiug hydrogen, oxy-chlopherc containing olefiant gas and the oxychlorid of chromium. -6. The herein described process of mnkin incandescent electric lamp filaments, whici consists in flushing the filament in an atmosphere contanun a hydrocarbon gas and the oxy-cblorid of c iromium.

7. The herein described process of nmlrin incandescent electric lamp filaments, whic ilmnent in an atmospherecontuinmg hydrogen ahydrocarbon gas, and ony-chlorid of ciroiuium.

8. The herein described process ofmukin incandescent electric lamp filaments, whio consists an flashing the filament in an atmosphere c'ontainin oxychlorid of chromium and an absorben' for the gases freed by the flnshin process.

9. '1 1e herein described process of mukin I incandescent electric lamp filaments, \vhic consists in 'flashing 0. iii icnt in an utmosoxy-ch orid of chromium and easeous n by the ashingsprocess.

10. The herein described recess of luck um filumcnts, w \ich consists in flushing the fi ament in an atmosphere contnin'in r oxy-chlcrid of chromium and anabsor nt for chlorin and oxygen. 4

HERSCI-TEL c. I-KRKER.

Witnesses:

WAnnaN B. Hu'ronmsox, FRANK'L- Swans.

orbent. for the gases freed 

